Split Discord bridge in multiple files (#632)

bridge/discord/helpers.go

@@ -0,0 +1,189 @@
+package bdiscord
+
+import (
+	"errors"
+	"regexp"
+	"strings"
+	"unicode"
+
+	"github.com/bwmarrin/discordgo"
+)
+
+func (b *Bdiscord) getNick(user *discordgo.User) string {
+	b.membersMutex.RLock()
+	defer b.membersMutex.RUnlock()
+
+	if member, ok := b.userMemberMap[user.ID]; ok {
+		if member.Nick != "" {
+			// Only return if nick is set.
+			return member.Nick
+		}
+		// Otherwise return username.
+		return user.Username
+	}
+
+	// If we didn't find nick, search for it.
+	member, err := b.c.GuildMember(b.guildID, user.ID)
+	if err != nil {
+		b.Log.Warnf("Failed to fetch information for member %#v: %#v", user, err)
+		return user.Username
+	} else if member == nil {
+		b.Log.Warnf("Got no information for member %#v", user)
+		return user.Username
+	}
+	b.userMemberMap[user.ID] = member
+	b.nickMemberMap[member.User.Username] = member
+	if member.Nick != "" {
+		b.nickMemberMap[member.Nick] = member
+		return member.Nick
+	}
+	return user.Username
+}
+
+func (b *Bdiscord) getGuildMemberByNick(nick string) (*discordgo.Member, error) {
+	b.membersMutex.RLock()
+	defer b.membersMutex.RUnlock()
+
+	if member, ok := b.nickMemberMap[nick]; ok {
+		return member, nil
+	}
+	return nil, errors.New("Couldn't find guild member with nick " + nick) // This will most likely get ignored by the caller
+}
+
+func (b *Bdiscord) getChannelID(name string) string {
+	b.channelsMutex.RLock()
+	defer b.channelsMutex.RUnlock()
+
+	idcheck := strings.Split(name, "ID:")
+	if len(idcheck) > 1 {
+		return idcheck[1]
+	}
+	for _, channel := range b.channels {
+		if channel.Name == name {
+			return channel.ID
+		}
+	}
+	return ""
+}
+
+func (b *Bdiscord) getChannelName(id string) string {
+	b.channelsMutex.RLock()
+	defer b.channelsMutex.RUnlock()
+
+	for _, channel := range b.channels {
+		if channel.ID == id {
+			return channel.Name
+		}
+	}
+	return ""
+}
+
+var (
+	// See https://discordapp.com/developers/docs/reference#message-formatting.
+	channelMentionRE = regexp.MustCompile("<#[0-9]+>")
+	emojiRE          = regexp.MustCompile("<(:.*?:)[0-9]+>")
+	userMentionRE    = regexp.MustCompile("@[^@\n]{1,32}")
+)
+
+func (b *Bdiscord) replaceChannelMentions(text string) string {
+	replaceChannelMentionFunc := func(match string) string {
+		var err error
+		channelID := match[2 : len(match)-1]
+
+		channelName := b.getChannelName(channelID)
+		// If we don't have the channel refresh our list.
+		if channelName == "" {
+			b.channels, err = b.c.GuildChannels(b.guildID)
+			if err != nil {
+				return "#unknownchannel"
+			}
+			channelName = b.getChannelName(channelID)
+		}
+		return "#" + channelName
+	}
+	return channelMentionRE.ReplaceAllStringFunc(text, replaceChannelMentionFunc)
+}
+
+func (b *Bdiscord) replaceUserMentions(text string) string {
+	replaceUserMentionFunc := func(match string) string {
+		var (
+			err      error
+			member   *discordgo.Member
+			username string
+		)
+
+		usernames := enumerateUsernames(match[1:])
+		for _, username = range usernames {
+			b.Log.Debugf("Testing mention: '%s'", username)
+			member, err = b.getGuildMemberByNick(username)
+			if err == nil {
+				break
+			}
+		}
+		if member == nil {
+			return match
+		}
+		return strings.Replace(match, "@"+username, member.User.Mention(), 1)
+	}
+	return userMentionRE.ReplaceAllStringFunc(text, replaceUserMentionFunc)
+}
+
+func (b *Bdiscord) stripCustomoji(text string) string {
+	return emojiRE.ReplaceAllString(text, `$1`)
+}
+
+func (b *Bdiscord) replaceAction(text string) (string, bool) {
+	if strings.HasPrefix(text, "_") && strings.HasSuffix(text, "_") {
+		return text[1:], true
+	}
+	return text, false
+}
+
+// splitURL splits a webhookURL and returns the ID and token.
+func (b *Bdiscord) splitURL(url string) (string, string) {
+	const (
+		expectedWebhookSplitCount = 7
+		webhookIdxID              = 5
+		webhookIdxToken           = 6
+	)
+	webhookURLSplit := strings.Split(url, "/")
+	if len(webhookURLSplit) != expectedWebhookSplitCount {
+		b.Log.Fatalf("%s is no correct discord WebhookURL", url)
+	}
+	return webhookURLSplit[webhookIdxID], webhookURLSplit[webhookIdxToken]
+}
+
+func enumerateUsernames(s string) []string {
+	onlySpace := true
+	for _, r := range s {
+		if !unicode.IsSpace(r) {
+			onlySpace = false
+			break
+		}
+	}
+	if onlySpace {
+		return nil
+	}
+
+	var username, endSpace string
+	var usernames []string
+	skippingSpace := true
+	for _, r := range s {
+		if unicode.IsSpace(r) {
+			if !skippingSpace {
+				usernames = append(usernames, username)
+				skippingSpace = true
+			}
+			endSpace += string(r)
+			username += string(r)
+		} else {
+			endSpace = ""
+			username += string(r)
+			skippingSpace = false
+		}
+	}
+	if endSpace == "" {
+		usernames = append(usernames, username)
+	}
+	return usernames
+}